System, method, and computer program product for indicating hostile fire

ABSTRACT

Systems, methods, and computer program products for identifying hostile fire. A characteristic of a fired projectile is detected using an optical system and the projectile&#39;s travel path in relation to a vehicle is determined. If the determined travel path of the projectile is within a predetermined distance from the vehicle, it is determined that the projectile is hostile towards the vehicle and a warning is output.

Embodiments of the invention relate generally to systems, methods, andcomputer program products for indicating hostile fire at a vehicle, forinstance, an aircraft. Embodiments of the invention also involve anetwork for indicating hostile fire and systems, methods, and computerprogram products thereof. Further, one or more embodiments of theinvention involve hostile fire damage assessment systems, methods, andcomputer program products.

SUMMARY

One or more embodiments of the present invention include a method forindicating hostile fire, comprising: electronically detecting infraredradiation of a projectile in a field of view (FOV); electronicallydetermining a travel path of the projectile based on the electronicallydetecting infrared radiation of the projectile in the FOV; comparing thedetermined travel path of the projectile to an electronic locationindication; and responsive to the comparing, electronically outputtingan indication that the projectile is hostile with respect to thelocation corresponding to the electronic location indication.

Optionally, the method can comprise, responsive to the comparing,automatically outputting control signals to initiate a countermeasuresystem. The location corresponding to the electronic location indicationcan be representative of a location of an airborne vehicle, forinstance, a helicopter, and the indication that the projectile ishostile can indicate that the projection will hit or will likely hit thevehicle. Further, the electronically detecting and the electronicallydetermining a travel path of the projectile can be performed by a camerawith an IR sensor, wherein a portion of the travel path may be indicatedas a two-dimensional representation over time.

Additionally, one or more embodiments can include a system operative onan airborne vehicle, for instance a helicopter, that is operative duringthe day and at night to determine whether the vehicle, while in flight,is an intended target of a fired unguided energetic projectile, thesystem comprising: a focal plane array (FPA) mounted to or onboard thevehicle, the FPA having a field of view (FOV) and a sensitivitysufficient to capture a firing signature of the fired unguided energeticprojectile, the firing signature including at least one of a firingcomponent generated upon firing of the projectile, a tracer-relatedcomponent associated with projectile pyrotechnics, and a frictioncomponent generated by friction as the projectile travels through thetroposphere, pixels of the FPA being operative to capture a portion of atrail of energy associated with the heat signature of the firedprojectile, the captured portion of the trail of energy being atwo-dimensional representation over time of a three-dimensionaltrajectory of the fired projectile projected onto the FPA; an imageprocessor located on board the vehicle operative to receive signals fromthe FPA corresponding to the captured portion of the trail of energy,the processor being operative to post-process in near real time thesignals from the FPA and to make a determination as to whether thein-flight vehicle was the intended target of the fired projectile byanalyzing the relationship of the captured portion of the trail ofenergy with respect to the FOV; and an alert system operatively coupledto the processor to generate timely audible and visible indications thatthe in-flight vehicle is the intended target of the fired projectile.The unguided energetic projectile may be any one of a rocket-propelledgrenade (RPG) in its ballistic phase of trajectory, for instance,anti-aircraft artillery (AAA), and small arms fire. The firing signaturemay be a heat signature of the projectile that can include, forinstance, at least one of the firing component generated upon firing ofthe projectile, the tracer-related component associated with projectilepyrotechnics, and the friction component generated by friction as theprojectile travels through the troposphere.

Optionally, the image processor is operative to determine estimatedvertical miss distance and/or horizontal miss distance of the firedprojectile with respect to the vehicle by analyzing correspondingcomponents of the captured portion of the trail of energy as functionsof time and velocity, for example, vehicle velocity and/or projectilevelocity. Optionally, the vehicle velocity may be subtracted from theequation. Further, in one or more embodiments of the present invention,the FOV can be adjustable in terms of direction and/or volumeindependent of the orientation of the vehicle. In one or moreembodiments the system can be configured and operative to capture andprocess multiple firing signatures from multiple fired projectiles andto determine whether any of the fired projectiles is intended for thevehicle. Optionally, the system can be configured and operative todetermine whether the projectile will hit, will likely hit, did hit,and/or did likely hit the vehicle. Put another way, the system can beconfigured and operative to determine whether the projectile will miss,will likely miss, did miss, and/or did likely miss the vehicle.

In one or more embodiments of the system, the system may comprise acountermeasure system onboard the vehicle that is operative to deployone of a soft-kill weapon, a non-lethal weapon, and a hard-kill weaponin response to the determination that the in-flight vehicle was theintended target of the fired projectile, the weapon being deployed to adetermined location or location area associated with the firedprojectile, wherein the determined location or location area isdetermined based on the signals from the FPA corresponding to thecaptured portion of the trail of energy. Optionally, the determinedlocation or location area is determined based on the signals from theFPA corresponding to the captured portion of the trail of energy andalso based on signals from an other FPA of the system, the other FPAhaving a field of view (FOV) and a sensitivity sufficient to capture aportion of the firing signature of the fired unguided energeticprojectile from the perspective of the other FPA, the firing signaturefrom the perspective of the other IR camera including at least one of afiring component generated upon firing of the projectile, atracer-related component associated with projectile pyrotechnics, and afriction component generated by friction as the projectile travelsthrough the troposphere, pixels of the other FPA being operative tocapture a portion of a trail of energy associated with the portion ofthe firing signature of the fired projectile from the perspective of theother FPA. The determined location or location area can be anorigination location or location area of the unguided energeticprojectile, and the image processor can be configured and operative toprocess signals from the FPA and the signals from the other FPA todetermine a distance to the origination location or location area of theunguided energetic projectile. Optionally, in addition to the twoaforementioned FPAs, one or more additional FPAs may implemented, forinstance, to determine the distance to the origination location orlocation area of the unguided energetic projectile.

Optionally, the system can also comprise one or more of a shock wavefront detection subsystem, a microphone array subsystem, anelectrostatic environment detection subsystem, and a radar detectionsubsystem. The system can also optionally comprise the infrared (IR)camera and at least one more of the IR cameras, each of the IR camerashaving a FOV, the FOVs combining to form a total FOV for the system.Alternatively, the system may include only IR detection components andnot the aforementioned shock wave front detection, microphone array,electrostatic environment detection, and radar detection subsystems, inorder to identify hostile fire aimed at the vehicle.

One or more embodiments of the invention can also include anon-transitory computer readable storage medium having stored thereonsoftware instructions that, when executed by a processor, cause theprocessor to perform operations comprising: analyze received electronicdata regarding a sensed heat signature portion of an unguidedprojectile; and determining a miss distance of the unguided projectilebased on the analyzed received electronic data, the miss distance beingone or more of of a vertical miss distance and a horizontal missdistance. The miss distance may be a calculated estimate of miss.Further, the heat signature portion may include one or more of a firingcomponent generated upon firing of the projectile, a tracer-relatedcomponent associated with projectile pyrotechnics, and a frictioncomponent. Optionally, the processor can be caused to perform operationscomprising: responsive to the determined miss distance of the unguidedprojectile, identify whether or not the unguided projectile is hostileor friendly; and in the case of a hostile identification, output anindication that the unguided projectile is hostile. Optionally, theprocessor can cause the follow operation: if the determining the missdistance indicates no miss, output an indication that the unguidedprojectile will be a hit or likely be a hit.

The miss distance may be with respect to a flying vehicle, can includeboth the vertical miss distance and the horizontal miss distance, andcan be determined by analyzing corresponding vertical and horizontalcomponents of the sensed heat signature as functions of time andvelocity, for example, vehicle velocity and/or projectile velocity.Optionally, the vehicle velocity may be subtracted from the equation.Further, optionally, the received electronic data is from an IR camerathat captures the sensed heat signature portion of the unguidedprojectile, the miss distance being calculated based on the sensed heatsignature within the FOV of the IR camera. In addition, the receivedelectronic data can optionally be from a plurality of IR cameras thatcapture respective portions of the heat signature of the unguidedprojectile in the FOVs, wherein the miss distance is calculated based onthe sensed heat signature portions sensed by the IR cameras. Each of theIR cameras may be spaced distances away from each other. Differences inthe displays of the IR cameras may be used to determine a range ordistance away from the vehicle of the location or location area fromwhich the projectile originated. Optionally, portions of the FOVs for atleast two IR cameras may overlap, for example, by five or ten degrees.

In one or more embodiments of the invention, a method for indicatinghostile fire, can comprise: receiving, at a first airborne vehicle,automatically transmitted hostile fire data regarding a second airbornevehicle, the automatically transmitted hostile fire data indicating thatthe second airborne vehicle is a target or likely target of hostilefire, the hostile fire data being derived from electronically detectedinfrared radiation associated with the hostile fire; and responsive tothe electronically receiving, automatically and electronicallyoutputting an output signal for remedial action of the first airbornevehicle. Optionally, the method can further comprise: prior to thereceiving at the first airborne vehicle, automatically transmittinghostile fire data regarding a second airborne vehicle; electronicallydetecting infrared radiation associated with the hostile fire in a fieldof view (FOV) of a camera with an IR sensor; electronically determiningthat the second airborne vehicle is the target or likely target ofhostile fire based on the electronically detected infrared radiationassociated with the hostile fire; and automatically transmitting thehostile fire data regarding the second airborne vehicle to at least thefirst airborne vehicle. Further, optionally, the first airborne vehiclemay electronically detect infrared radiation associated with the hostilefire in a FOV of its own camera or cameras with corresponding IRsensors. Data obtained from such sensing, whether or not processed todetermine whether the first airborne vehicle is the target or likelytarget of the hostile fire, may be transmitted to the second airbornevehicle. Thus, information may be transmitted in both directions betweenthe two platforms of the airborne vehicles (at least these twovehicles). Such shared information may be used to obtain initial orbetter accuracy with respect a location or location area of the hostilefire and/or a distance to the location or location area of the hostilefire.

The output signal for remedial action can be for activation of one ormore of a tactile display (e.g., a matrix of vibrating or buzzingelements in a vest, a seat, etc.), a visual alert, an audible alert, acountermeasure system, a transmission operation of hostile fire dataregarding the second airborne vehicle from the first airborne vehicle toa third airborne vehicle, a data recording system, an evasive maneuversystem, and a de-engagement of autopilot. Further, optionally, theautomatically transmitted hostile fire data indicating that the secondairborne vehicle is a target or likely target of hostile fire may bebased on a probability calculation regarding whether the hostile firewill hit, will likely hit, will miss, or will likely miss the secondairborne vehicle. The received hostile fire data at the first airbornevehicle regarding a second airborne vehicle can include data regarding ahit location or likely hit location on the second airborne vehicle ofthe hostile fire.

The invention can also include one or more embodiments involving anetwork for communicating detection of hostile fire, the networkcomprising: a first helicopter system onboard a first helicopter, thefirst helicopter system being operative during the day and at night todetermine whether the first helicopter, while in flight, is an intendedtarget of a fired unguided energetic projectile. The first helicoptersystem can include: an infrared (IR) camera, the IR camera having afield of view (FOV) and a predetermined sensitivity sufficient tocapture a portion of a heat signature of the fired unguided energeticprojectile, the heat signature including at least one of a firingcomponent generated upon firing of the projectile, a tracer-relatedcomponent associated with projectile pyrotechnics, and a frictioncomponent generated by friction as the projectile travels through thetroposphere, pixels of the IR camera being operative to capture aportion of a trail of energy associated with the heat signature of thefired projectile, the captured portion of the trail of energy being atwo-dimensional representation over time of the projectile; an imageprocessor located on board the first helicopter and operative to receivesignals from the IR camera corresponding to the captured portion of thetrail of energy, the processor being operative to post-process in nearreal time the signals from the IR camera and to make a determination asto whether the in-flight helicopter was the intended target of the firedprojectile by analyzing the relationship of the captured portion of thetrail of energy with respect to the FOV of the IR camera, the pixels ofthe IR camera being mapped to angles in the FOV; and a transmitter totransmit to a second helicopter system onboard a second helicopter ofthe network signals indicating that the first helicopter is subject tohostile fire. The unguided energetic projectile may be any one of arocket-propelled grenade (RPG) in its ballistic phase of trajectory, forinstance, anti-aircraft artillery (AAA), and small arms fire.

Optionally, the second helicopter system can include: a receiver toreceive the signals indicating that the first helicopter is subject tohostile fire; and an alert system operatively to generate timelyaudible, visible, and/or tactile hostile fire indications in response tothe received signals indicating that the first helicopter is subject tohostile fire. The tactile display can include a matrix of vibrating orbuzzing elements in a vest, a seat, etc., for example.

In one or more embodiments, the transmitter can transmit signalsindicating that the first helicopter is subject to hostile fire to thesecond helicopter system and to one or more additional helicoptersystems onboard respective one or more helicopters and/or to one or moreadditional non-helicopter aircraft systems. Further, optionally, theimage processor of the first helicopter system may be operative todetermine vertical and/or horizontal miss distances of the firedprojectile with respect to the first helicopter by analyzingcorresponding horizontal and vertical components of the captured portionof the trail of energy as functions of time and velocity, for example,first helicopter velocity and/or projectile velocity.

In one or more embodiments, the transmitter of the first helicoptersystem can be operative to transmit data associated with a determinedlocation or location area associated with the fired projectile to thesecond helicopter system, the determined location or location area beingdetermined based on the signals from the IR camera corresponding to thecaptured portion of the trail of energy, and wherein the secondhelicopter system can include: a receiver to receive the signalsindicating that the first helicopter is subject to hostile fire and thedetermined location or location area data; and a countermeasure systemonboard the second helicopter that is operative to deploy one of asoft-kill weapon, a non-level weapon, and a hard-kill weapon in responseto the determination that the first helicopter was subject to hostilefire, the weapon being deployed to the determined location or locationarea associated with the fired projectile.

For one or more embodiments, the first helicopter system can beconfigured and operative to capture and process multiple heat signaturesfrom multiple fired projectiles and to determine whether any of thefired projectiles is intended for the first helicopter. Additionally,for one or more embodiments, the second helicopter system can include adata storage unit to electronically store data from the first helicoptersystem regarding flight data of the first helicopter, the flight dataincluding one or more of a flight path, a velocity, an altitude, anorientation, a time, and a location of the first helicopter in relationto the fired unguided energetic projectile. Optionally, the associationof the fired unguided energetic projectile and the flight data of thefirst helicopter may be with respect to a determined location orlocation area of an origin of the fired unguided energetic projectile,the determined location or location area being determined by the imageprocessor of the first helicopter and transmitted via the transmitter ofthe first helicopter system to the second helicopter system.

Optionally, the second helicopter system can include: an infrared (IR)camera mounted to the second military helicopter, the IR camera having afield of view (FOV) and a predetermined sensitivity sufficient tocapture a heat signature of the fired unguided energetic projectile, theheat signature including at least one of a firing component generatedupon firing of the projectile, a tracer-related component associatedwith projectile pyrotechnics, and a friction component, pixels of the IRcamera being operative to capture a portion of a trail of energyassociated with the heat signature of the fired projectile, the capturedportion of the trail of energy being a two-dimensional representationover time of a portion of the trajectory of the fired projectile; and animage processor located on board the second helicopter and operative toreceive signals from the IR camera corresponding to the captured portionof the trail of energy, the processor being operative to post-process innear real time the signals from the IR camera and to make adetermination as to whether the second helicopter was the intendedtarget of the fired projectile by analyzing the relationship of thecaptured portion of the trail of energy with respect to the FOV of theIR camera; and a transmitter to transmit to the first helicopter systemsignals indicating that the second helicopter is subject to hostilefire. The first helicopter system can be operative to determine alocation or location area of an origin of the fired unguided energeticprojectile based on the post-processed signals from the IR camera of thefirst helicopter system and from the post-processed signals from the IRcamera of the second helicopter system received by the first helicoptersystem. Additionally, the second helicopter system can be operative todetermine the location or location area of the origin of the firedunguided energetic projectile based on the post-processed signals fromthe IR camera of the second helicopter system and from post-processedsignals from the IR camera of the first helicopter system received bythe second helicopter system.

One or more embodiments of the present invention also include anon-transitory computer readable storage medium having stored thereonsoftware instructions that, when executed by a processor, cause theprocessor to perform operations comprising: receiving signals indicativeof whether or not a second vehicle, remotely located with respect to afirst vehicle having the processor, is an intended target of a firedprojectile, for example, a fired, ground-based projectile, the receivedsignals being based on a thermally sensed travel path portion of thefired projectile with respect to a FOV of a focal plane array (FPA); andelectronically processing the received signals. Optionally, theelectronically processing includes storing data corresponding to thereceived intended target signals in an electronic storage medium, thestored data indicating one of a miss distance of the fired projectile orhit data with respect to the second vehicle.

For one or more embodiments, the electronically processing the receivedsignals can cause the processor to perform one or more of the followingoperations: output a signal to cause a visual alert, output a signal tocause an audible alert, output a signal to activate a tactile display(e.g., a matrix of vibrating or buzzing elements in a vest, a seat,etc.), output a signal to activate a countermeasure system, output asignal to transmit data regarding whether or not the second vehicle isthe intended target of the fired projectile to another vehicle, output asignal to cause a visual instruction (e.g., in virtual or hologram formor on a visual display, such as a heads-up display (HUD), and output asignal to cause an audible instruction.

Optionally, the electronically processing the received signals mayinclude determining a location of origin for the fired projectile.Additionally, optionally, the processor may be operative to performoperations comprising: receiving signals indicative of whether or notone or more additional vehicles remotely located with respect to a firstvehicle having the processor, other than the second vehicle, areintended targets of fired projectiles, the received signals being basedon a thermally sensed travel path portion of the fired projectile withrespect to a field of view (FOV) of a focal plane array (FPA); andelectronically processing the received signals.

Additionally, one or more embodiments of the invention can include ahelicopter maintenance system that is operative to determine whether thehelicopter, while in flight, was hit or was likely hit by a firedunguided energetic projectile and the position or likely position on thehelicopter where the projectile hit or likely hit. Such determinationcan be used as part of an in-flight damage indication and assessmentsystem. Optionally or alternatively, such determination can be used aspart of a post-flight maintenance damage indication and assessmentsystem. The system can comprise: an infrared (IR) camera mounted to thehelicopter, the IR camera having a field of view (FOV) and apredetermined sensitivity sufficient to capture a heat signature of thefired unguided energetic projectile, the heat signature including atleast one of a firing component generated upon firing of the projectile,a tracer-related component, and a friction component, pixels of the IRcamera being operative to capture a portion of a trail of energyassociated with the heat signature of the fired projectile, the capturedportion of the trail of energy being a two-dimensional representationover time of a trajectory portion of the fired projectile; an imageprocessor located on board the helicopter and operative to receivesignals from the IR camera corresponding to the captured portion of thetrail of energy, the processor being operative to post-process thesignals from the IR camera and to make a determination as to whether thefired projectile hit or likely hit the helicopter and the position orlikely position on the helicopter where the projectile hit or likely hitthe helicopter by analyzing the relationship of the captured portion ofthe trail of energy with respect to the FOV of the IR camera, and anelectronic data storage device to store data regarding projectile hitposition or likely hit position on the helicopter, the electronic datastorage device being accessible when the helicopter is not in flight.Optionally, the system can comprise an alert system operatively coupledto the image processor to generate timely audible and/or visibleindications that the helicopter was hit or was likely hit by the firedprojectile.

In one or more embodiments, the stored data regarding projectile hitposition or likely hit position on the helicopter may be retrievable forperformance of a post-flight inspection. Optionally, the electronic datastorage device can be accessible by ground crew maintenance personnel.Optionally or alternatively, the stored data may be for in-flight damageassessment. The accessing the electronic data storage device by theground crew maintenance personnel may include displaying of a diagram ofthe aircraft (e.g., a helicopter) on a display screen and showingindicia on the diagram representative of one or more hit or likely hitpositions on the helicopter. Further, the position or likely position onthe helicopter is a zone of the helicopter. Optionally, the unguidedenergetic projectile is any one of a rocket-propelled grenade (RPG),anti-aircraft artillery (AAA), and small arms fire.

In one or more embodiments of the invention, the system is configuredand operative to capture and process multiple projectile signatures(e.g., heat or infrared light signatures) from multiple firedprojectiles and to determine whether any of the fired projectiles hit orlikely hit the helicopter and the corresponding positions or likelypositions on the helicopter where any of the projectiles hit or likelyhit. Hit or likely hit data from accessing the electronic data storagedevice may be for providing a map of the helicopter showing any of oneor more hit or likely hit positions of fired projectiles with respect tothe helicopter. Further, the map may include more than one view of thehelicopter and corresponding any of one or more hit or likely hitpositions. Thus, in one or more embodiments, hit probability data can beproduced. Such data can used in-flight for damage estimates and/or forprobability of hit assessment.

Further, included among one or more embodiments also is a method forindicating damage caused by a fired projectile, comprising:electronically detecting infrared radiation of a projectile in a fieldof view (FOV); electronically determining a travel path of theprojectile based on the electronically detecting infrared radiation ofthe projectile in the FOV; responsive to the electronically determininga travel path, generating probabilistic data regarding likelihood of theprojectile hitting a vehicle associated with the FOV; and generating anindication based on the probabilistic data. The indication may be anaudible and/or a visual warning to an operator of the vehicle warningthe operator to control the vehicle so as to take evasive action.Further, optionally, the indication may also be a tactile display, forinstance, an individual or a matrix of vibrating or buzzing elements ina vest, a seat, etc.

Optionally, the probabilistic data can indicate that the vehicle waslikely hit, the likely hit probabilistic data being indicated by a hitprobability that exceeds a threshold amount. Optionally oralternatively, the probabilistic data indicates that the vehicle willlikely be hit, the likely hit probabilistic data being indicated by ahit probability that exceeds a threshold amount. Optionally oralternatively, the probabilistic data is indicative of the projectilehitting or likely hitting the vehicle, and the indication is for an airor a maintenance crew member indicating that the helicopter was hit orwas likely hit and an approximation or estimation of where thehelicopter was hit or was likely hit for post-flight inspection andrepair. The probabilistic data may also be used for in-flight damagelocation indication and assessment.

In one or more embodiments of the invention, a nontransitory computerreadable storage medium having stored thereon software instructionsthat, when executed by a processor, can cause the processor to performoperations comprising: analyze received electronic data regarding anysensed heat signatures of small arms fire sensed in a predeterminedsensing zone; determine any hit locations or probably hit locations ofsmall arms fire based on estimations of associated paths of the smallarms fire with respect to a focal plane array; and electronically storedata corresponding to any determined hit locations or probably hitlocations for later retrieval and analysis. The received electronic datamay be in terms of one or more functions of time of a flying vehicleand/or one or more functions of velocity of the flying vehicle and/orthe velocity of the projectile, for instance.

Optionally, the instructions, when executed by the processor, can causethe processor to perform operations comprising: responsive to aretrieval request, output the stored data corresponding to anydetermined hit or probable hit locations for later retrieval andanalysis, the stored data being transformed so as to provide on adisplay device a visual diagrammatic representation of the flyingvehicle and any determined hit locations or probably hit locations tothe flying vehicle. Further, optionally, the instructions, when executedby the processor, cause the processor to perform operations comprising:outputting on the display device a sequence of inspection instructionsfor each of the determined hit locations. Optionally, the display deviceis a hand-held display device.

Embodiments also include computer program products or non-transitorycomputer readable media that can perform some or all aspects orfunctionality of methods, circuitry, circuits, systems, or systemcomponents as set forth herein and according to embodiments of thedisclosed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will hereinafter be described in detailbelow with reference to the accompanying drawings, wherein likereference numerals represent like elements. The accompanying drawingshave not necessarily been drawn to scale. Any values dimensionsillustrated in the accompanying graphs and figures are for illustrationpurposes only and may or may not represent actual or preferred values ordimensions. Where applicable, some or all features may not beillustrated to assist in the description of underlying features.

FIG. 1 is a block diagram of a system according to one or moreembodiments of the invention.

FIGS. 2A and 2B are operational depictions of systems, methods, andcomputer program products according to one or more embodiments of theinvention.

FIGS. 3A through 3C are graphs showing examples of projectile trajectorydata.

FIG. 4 is a flow chart for a method according to one or more embodimentsof the invention.

FIG. 5 is a flow chart for a method according to one or more embodimentsof the invention.

FIG. 6 is a flow chart for method according to one or more embodimentsof the invention.

FIG. 7 is an operational depiction of a network and system, method, andcomputer program product thereof according to one or more embodiments ofthe invention.

FIG. 8 is an example of a display according to a maintenance and/orinflight hit and damage assessment system, method, and computer programproduct according to one or more embodiments of the invention.

FIGS. 9A-9D and 10A-10D show data regarding different operationalscenarios according to one or more embodiments of the invention.

DESCRIPTION

The description set forth below in connection with the appended drawingsis intended as a description of various embodiments of the invention andis not necessarily intended to represent the only embodiments in whichthe invention may be practiced. In certain instances, the descriptionincludes specific details for the purpose of providing an understandingof the invention. However, it will be apparent to those skilled in theart that the invention may be practiced without these specific details.In some instances, well-known structures and components may be shown inblock diagram form in order to avoid obscuring the concepts of thedisclosed subject matter.

Generally speaking, embodiments of the invention relate to systems,methods, and computer program products for identifying and indicatinghostile fire. Embodiments of the invention also involve a network foridentifying, indicating, and communicating (i.e., transmitting andreceiving) hostile fire data, and systems, methods, and computer programproducts thereof. Further, one or more embodiments of the inventioninvolve hostile fire damage assessment systems, methods, and computerprogram products, for instance, for in-flight and/or post-flight damageindication and assessment.

Hostile fire may include fire directed or aimed at a particular vehicle.Thus, embodiments of the invention can provide the ability to not onlypositively detect the firing of projectiles in the vicinity of avehicle, but also to determine whether the projectile associated withthe detected firing is approaching the vehicle and optionally is athreat to the vehicle. Further, optionally, hostile fire may include asituation where a projectile trajectory is determined to pass within apredetermined distance away from the vehicle. Optionally, hostile firemay include a situation where it is determined that the projectilewill/will likely or has/has likely hit the vehicle. Hostile fire,optionally, may include a situation where it is determined that theprojectile is threatening/likely threatening or lethal/likely lethal,the latter of which not necessarily indicating downing or substantiallytotal destruction or incapacitation of the vehicle. Accordingly, one ormore embodiments of the invention can distinguish between hostile fireand friendly fire, fire from an enemy combatant not aimed at thevehicle, or fire otherwise non-threatening or lethal to the vehicle, forinstance, if the projectile is not likely to hit the vehicle or outsideits lethal range.

A vehicle or vehicles according to one or more embodiments of theinvention can include a helicopter, an airplane, an unmanned aerialvehicle (UAV), or a land-based vehicle, such as a tank or a highmobility multipurpose wheeled vehicle (HMMWV). In an alternativeembodiment, the “vehicle” may be substituted for by a person, and thesystem, method, or computer program product according to one or moreembodiments of the invention can determine whether the person is theintended target or likely target of hostile fire.

Hostile fire detectable according to one or more embodiments of theinvention can be ballistic or energetic projectiles, including one ormore of each of a rocket-propelled grenade (RPG) in a ballistic phase ofits trajectory, for instance, anti-aircraft artillery (AAA), and smallarms fire (e.g., from an automatic rifle), for example. The foregoing,of course, are non-limiting examples. The small arms fire may or may nothave a tracer-related component. Thus, in embodiments of the presentinvention, hostile fire from small arms fire not having a tracercomponent may be detected and identified. For example, a single-shotbullet not having a tracer component may be detected and identified, forinstance, using only one optical detector, sensor, or receiver accordingto one or more embodiments of the present invention.

FIG. 1 is a block diagram a system 100 according to one or moreembodiments of the invention. System 100 can be implemented in avehicle, such as a helicopter 200 (See, e.g., FIGS. 2A and 2B).Incidentally, helicopter 200 may be a military helicopter, a lawenforcement or private security helicopter, or a civilian helicopter(e.g., flying in a restricted area and possibly subject to hostilefire). Of course, system 100 may be implemented with other aircraft,such as an airplane, a jet, a glider, an unmanned aerial vehicle (UAV),a blimp, or the like. Further, in one or more embodiments, system 100can be implemented in land- or water-based vehicles, such as trucks,tanks, hovercrafts, or the like. As indicated above, system 100 may beimplemented onboard a person (e.g., a soldier). System 100 can beoperative and effective during day and night conditions, for instance.

System 100 can include a threat detection and identification subsystem102, a communication subsystem 104, an information output subsystem 105,and a controller 106. In one or more embodiments of the invention, oneor more components of the system 100 can be implemented in componentsalready installed on the vehicle and may not require any additionalhardware.

Threat detection and identification subsystem 102 can include an opticaldetector, sensor, or receiver, such as a thermographic camera orinfrared (IR) camera, also called a focal plane array (FPA). The opticaldetector can have a field of view (FOV), for instance, 100 to 105degrees, and sensitivity sufficient to capture firing signature(s) offired projectile(s). Optionally, the optical detector/sensor/receivermay be the only one of such detectors on the vehicle, and threatdetection and identification may be performed based on data input to orreceived by the single optical detector only. Alternatively, the threatdetection and identification subsystem 102 may include more than oneoptical detector/sensor/receiver, but still the threat detection andidentification may be performed based on data input to or received byonly one of the single optical detectors.

Firing signature can be a heat signature of the projectile sensed by theFPA. Further, the heat signature can represent a portion of theprojectile trajectory, wherein portion can be an entire portion thereoffrom origination (e.g., muzzle flash) to where the projectile leaves theFOV or hits the FPA; a portion from a predetermined distance away fromthe vehicle (e.g., 100 or 200 meters away) to where the projectileleaves the FOV (or hits the FPA) and not the muzzle flash; a portionfrom the muzzle flash and then not again until the projectile is apredetermined distance away from the vehicle (e.g., 100 or 200 metersaway) to where the projectile leaves the FOV (or hits the FPA); and aportion from where the projectile enters the FOV to when it leaves theFOV. Thus, portions of the heat signature can include infrared radiationin the form of one or more of a firing component generated upon firingof the projectile (e.g., a muzzle flash), a tracer-related componentassociated with projectile pyrotechnics, and a friction componentgenerated by friction as the projectile travels through the troposphere(e.g., a heat trail). The friction component, for instance, may not be“visible” by the FPA until it is a predetermined distance away from theFPA. Further, the trail may be substantially straight lined or havestraight line portions, or it may be curved or have curved portions(e.g., arc or parabolic). Pixels of the FPA are operative to capture aportion of a trail of energy corresponding to the portion of the heatsignature of the fired projectile. The captured portion of the trail ofenergy is a two-dimensional representation over time of athree-dimensional trajectory of the fired projectile projected onto theFPA.

As will be discussed in more detail below, threat detection andidentification subsystem 102 can include more than one optical detector,such as two, four, eight, or more optical detectors. Each of the opticaldetectors can have their own FOVs (of same or differing FOVs as otheroptical detectors) to form a total FOV. The FOVs can form a total FOVfor the threat detection and identification subsystem 102, for instance,for 180 degrees of coverage. Optionally, some or all adjacent FOVs mayoverlap, for example, by five to ten degrees. Further, one or more ofthe FOVs may be moved, for example, mechanically by physically moving aportion of the corresponding optical detector, or electronically, viasoftware, for instance. Further, one or more of the FOVs may bemodified, for instance, expanded or contracted, extended or withdrawn,widened or narrowed, and/or turned on or turned off.

Optionally, system 100 can also comprise one or more additional threatdetection and/or identification subsystems, including a shock wave frontdetection subsystem, a microphone array subsystem, an electrostaticenvironment detection subsystem, a radar detection subsystem, and amuzzle flash detection subsystem. For example, threat detection andidentification subsystem 102 may be operative with a separate muzzleflash detection subsystem, whereby the muzzle flash detection subsystemcan cue the threat detection and identification subsystem 102 todetermine whether the fired projectile is hostile or not. Thus, one ormore algorithms associated with the threat detection and identificationsubsystem 102 may work with one or more algorithms associated with oneor more of additional threat detection and/or identification subsystems,such as a separate muzzle flash detection subsystem. Optionally, one ormore algorithms associated with the threat detection and identificationsubsystem 102 may be “on” the same optical detector, sensor, or receiveras one or more additional algorithms associated with muzzle flashdetection. Optionally or alternatively, system 100 may include only IRdetection components for the threat detect and identification subsystem102 and not the aforementioned shock wave front detection subsystem,microphone array subsystem, electrostatic environment detectionsubsystem, and radar detection subsystem, in order to detect andidentify hostile fire regarding the vehicle.

Controller 106 can be a processor, for instance, an image processor,located onboard a vehicle associated with system 100. Generallyspeaking, the controller 106 can execute computer executableinstructions running thereon or provided from an external source, frominternal and/or external memory. Controller 106 can be implemented onone or more general purpose networked computer systems, embeddedcomputer systems, routers, switches, server devices, client devices,various intermediate devices/nodes and/or stand-alone computer systems.Controller 106 can be a computerized controller or microcontroller witha processor or processors. Further, controller 106 can include and/or becoupled to volatile and non-volatile memory 107. Dual microprocessorsand other multi-processor architectures can also be utilized as theprocessor. The processor(s) and memory 107 can be coupled by any ofseveral types of bus structures, including a memory bus or memorycontroller, a peripheral bus, and a local bus using any of a variety ofbus architectures. The memory 107 can include read only memory (ROM) andrandom access memory (RAM), for instance. Optionally, controller 106 orsystem 100 in general can include one or more types of long-term datastorage units. The long-term data storage can be connected to thecontroller 106 by an interface. Optionally or alternatively, some or allof the data storage may be internal of the controller 106 and can becoupled to the processor(s) by a drive interface or interfaces. Thelong-term storage components can provide nonvolatile storage of data,data structures, and computer-executable instructions for the controller106 and more specifically the processor(s) of the controller 106. Anumber of program modules may also be stored in one or more of thedrives as well as in the RAM, including an operating system, one or moreapplication programs, other program modules, and program data.

Controller 106 can be operative to receive signals from the threatdetection and identification subsystem 102. Optionally, controller 106can receive signals from one or more additional threat detectionsubsystems as set forth herein. Further, optionally or alternatively,threat detection and identification subsystem 102 may have a processor,for example, an image processor, to perform some or all of thepost-detection processing and send corresponding data signals tocontroller 106.

The controller 106 can be operative to post-process in substantiallyreal time or near real time, for instance, signals from the threatdetection and identification subsystem 102 (and optionally one or moreadditional threat detection subsystems) and to determine whether a firedtrajectory is hostile with respect to the corresponding vehicle ofsystem 100. Optionally, controller 106 can determine whether the vehiclewas hit or likely hit based on signals from the threat detection andidentification subsystem 102 (and optionally one or more additionalthreat detection subsystems).

In the case of received signals from an FPA (or optionally multipleFPAs), these signals can correspond to the captured portion(s) of atrail of energy associated with the projectile heat signature. Based atleast on those signals, the controller 106 may determine whether theprojectile is hostile or not.

Controller 106 can also provide data, such as control data, to threatdetection and identification subsystem 102. Further, controller 106 canreceive data from and send data to vehicle-specific subsystems, such asnavigation, flight control, audio and/or visual, weaponry, andcountermeasure subsystems (not expressly shown), as well ascommunication subsystem 104 and an information output subsystem 105,and, optionally, any of such data may be provided to the threatdetection and identification subsystem 102 in order perform processingor calculations for its detection and identification of hostile fire.

Communication subsystem 104 can be a communication system forcommunicating data to and from one or more locations remote from thesystem 100 and the corresponding vehicle. Communication subsystem 104can send and/or receive data in one or more of omni-directional formator directed format. Corresponding receivers and transmitters andassociated components and circuitry (e.g., filters, tuners, antennas,etc.) can be employed. In one or more embodiments, the communicationsubsystem 104 is onboard the vehicle and can send hostile fire detectionand/or indication data as set forth herein to one or more other vehicles(e.g., another helicopter) in a network of vehicles. Such hostile firedetection and/or indication data can be used by the other vehicle(s) totake appropriate actions, such as rerouting, deploying countermeasures,deploying weapons systems, and/or determining a location of and/ordistance to the origination of the hostile fire.

Information output subsystem 105 can represent multiple outputsubsystems. For example, information output subsystem 105 can include analert, warning, or indication (e.g., visual, audible, and/or tactile) tooccupants of vehicle that the vehicle is an intended target of a firedweapon and/or that the projectile is potentially damaging or lethal, forinstance, based on detected projectile characteristics. Further, thetype of weapon associated with the projectile may also be indicated. Avisual alert or warning may be displayed on a computer screen or a headsup display (HUD) of the vehicle, for instance. The tactile display maybe an individual or a matrix of vibrating or buzzing elements in a vestor a seat, for instance, of a pilot and/or copilot. Such alert, warning,or indication can be used to take appropriate actions, such asrerouting, deploying countermeasures, and/or deploying weapons systemsof the vehicle. Further, in one or more embodiments, information outputsubsystem 105 can be for post-trip activities, such as to analyzecharacteristics of a mission (e.g., a location where the vehicleexperienced hostile fire) or for inspection or maintenance purposes. Forexample, hostile fire data, such as a location or an area on the vehiclewhere hostile fire hit or likely hit the vehicle can be displayed somaintenance personnel can perform inspections and/or maintenance to thelocation or area or associated components. In-flight damage assessmentalso may be performed based output(s) of information output subsystem105.

System 100 may determine projectile miss distance, and based on the missdistance, i.e., whether the projectile is a predetermined or predefineddistance away from the corresponding vehicle associated with system 100,system 100 can determine and indicate that the projectile is hostile.Vertical and/or horizontal miss distance may be determined. Further,optionally, system 100, for instance, controller 106, also may calculatestatistical or probabilistic data regarding a hit or likely hit to thevehicle by the projectile based on the data from the threat detectionsubsystem 102.

As indicated above, IR camera(s) or FPA(s) may be included as part ofthe threat detection and identification subsystem 102 and can be used tomeasure projectile miss distance, for instance, indirectly. Regarding IRcameras or FPAs, these devices can “see” “angle space.” That is, thepixels of the FPA can be mapped to angles in the FOV of the FPA.Further, tracks of the FPA can be analyzed to calibrate the FPA and seta threshold or thresholds based on known velocities or velocity rangesof projectiles and corresponding distance ranges, for example, lethal orthreatening projectile ranges. Optionally, constant or relativelyconstant velocity assumptions regarding projectiles and theircorresponding caliber may be used. Further, because lethal orthreatening ranges of projectiles are known, projectile data may beplaced in caliber- and/or range-dependent bins for use in determiningmiss distance. For example, velocity (or estimated velocity) and rangedata for a fifty caliber projectile may be stored in a bin for later-usein determining miss distance of the projectile. As another example, forRPGs, which have a velocity profile dependent upon whether thepropellant is active or not, the ballistic portion of the trajectory maybe sorted out and such data can be stored in a corresponding bin forlater use in determining miss distance of the projectile. System 100 mayascertain projectile data and put projectile data representingprojectile characteristics in one or more bins. If the projectile wasfired within its lethal or threatening range, its velocity can fallwithin the corresponding bin and therefore its minimum range was withinthe corresponding bin. Accordingly, because system 100 knows thevelocity of the projectile, the projectile distance from the vehicle canbe determined. Optionally, projectile data (e.g., velocity, trajectoryprofile, etc.) may be captured and stored by the FPA(s) for updating orcreating new caliber- and/or range-dependent bins.

FIGS. 3A through 3C are graphs showing exemplary projectile trajectorydata as seen by a focal plane array (FPA) according to one or moreembodiments of the invention. FIG. 3A is representative of a projectileabove the vehicle sensor centerline, a helicopter-mounted sensor in thisexample, FIG. 3B is a representation of cross-track trajectory (pixelsvs. time) of the projectile passing the helicopter sensor centerlineposition HELO in horizontal direction, and FIG. 3C is a representationof vertical trajectory (pixels vs. time) of the projectile passing thehelicopter sensor centerline position HELO in vertical direction. In theexample shown in FIGS. 3A to 3C, the projectile trajectory is above thehelicopter HELO sensor centerline. The vertical and/or horizontal missdistances of the projectile, as it passes the helicopter HELO sensorcenterline, can be determined by analyzing both the horizontal andvertical pixel trail in the array as functions of time and projectilevelocity, for instance. Optionally, though the velocity of the vehiclemay be relatively small as compared to that of the projectile, vehiclevelocity may also be factored in, for example “subtracted” from thepixel view. Optionally, the system may determine a direction of travelfor each of the detected projectiles.

Miss distance may be measured or calculated based on the rate of changethe projectile trace (first derivative) and the rate of rate of changeof the projectile trace (second derivative) in the FPA, respectivelyrepresented by the following:

$\left( \frac{\Delta \; {pixels}}{\Delta \; {frames}} \right)\mspace{14mu} {and}\mspace{14mu} \left( \frac{\Delta^{2}{pixels}}{\Delta \; {frames}^{2}} \right)$

The product of the foregoing terms can represent the miss distance, andif the product of these two terms is “high,” then the bullet has passedclose or even has or may have hit the vehicle.

$\left( \frac{\Delta \mspace{14mu} {pixels}}{\Delta \; {frames}} \right)*\left( \frac{\Delta^{2}{pixels}}{\Delta \; {frames}^{2}} \right)$

The determined miss distance may be compared to a predetermined distancethreshold, for instance by controller 110. If the determined missdistance is at or above the threshold, this can indicate that theprojectile was aimed at or intended to hit the vehicle, for example. Aswill be discussed in more detail below, such an indication can causefurther actions to be taken, such as outputting audible, visible, and/ortactile alerts, activating countermeasures or weapons, transmittinghostile fire data to a location or locations remote from the vehicle,providing instructions for rerouting or taking evasive action,determining a location or distance to the origination of the hostilefire, etc.

FIGS. 9A-9D and 10A-10D show data regarding projectile trajectory missdistance as seen from an FPA of a vehicle, also a helicopter HELO inthese figures.

FIG. 9A shows trajectories associated with projectiles P1-P3 fromdifferent directions D1-D3, respectively, which cross a focal plane ofan optical sensor onboard the vehicle, each of which at a closestdistance away from the helicopter HELO of ten meters away. Similarly,FIG. 9B shows trajectories associated with projectiles P1-P3 fromdifferent directions D1-D3, respectively, which cross the focal plane,each of which at a closest distance away from the helicopter HELO offifty meters. The concentric rings surrounding the helicopter HELO showdistances away from the helicopter HELO, ten, thirty, fifty, seventy,and one hundred meters, respectively. Incidentally, for the scenarios inFIGS. 9A and 9B, the projectiles P1-P3 are visible to the FPA at onehundred meters out, the projectile velocity is one thousandmeters/second, the FPA has one thousand pixels, and the frame rate ofthe FPA is one thousand FPS. The characteristics set forth in thesescenarios, however, are merely examples and not intended to be limiting.For instance, the FPA may “see” the projectiles initially from distancesgreater than or less than one hundred meters out, the projectilevelocity may be more or less than one thousand meters/second, the FPAmay have more or less than one thousand pixels, for instance, and/or theFPA frame rate may be less than or greater than one thousand FPS.

In FIGS. 9B, 9C, and 9D, the top graph 900 indicates the projectiletrace on the FPA for each of the projectiles P1, P3, and P3 when theprojectile miss distance is ten meters. Similarly, in FIGS. 10B, 10C,and 10D, the top graph 1000 indicates the projectile trace on the FPAfor each of the projectiles P1, P3, and P3 when the projectile missdistance is fifty meters. Graphs 902, 904, 906 and 1002, 1004, 1006 showobserved x-axis bullet traces, wherein 902/1002 represent projectilerate of change (first derivative), 904/1004 represent rate of rate ofchange (second derivative), and 906/1006 represent products of the twoderivatives. The sign of the product indicates approaching or recedingprojectiles, wherein a positive sign means approaching and a negativesign means receding. As discussed above, the magnitude of the productindicates closest proximity within the FPA's FOV and is angleindependent. In the case of FIGS. 9A-9D, the miss distance is ten metersand the corresponding product of the derivatives is forty five. In FIGS.10A-10D, the miss distance is fifty meters and the corresponding productof the derivatives is 0.5, less than the previous value for a missdistance of ten meters.

Turning now to FIG. 2A, this figure shows an operational example of asystem according to embodiments of the invention (e.g., system 100) onboard a helicopter 200 outfitted with an IR camera 202 with anoutwardly-directed field of view FOV 203. Actors 202 and 203 are enemycombatants, whereas actor 201 is a friendly. As can be seen in FIG. 2A,actor 202 is aiming at helicopter 200, but actors 201 and 203 are not(though actor 203 is indeed an enemy combatant). In this particularexample, the system may detect and identify the firing from actor 202 ashostile. Further, even if fire from either actor 201 and/or 203 isdetected for example, because the corresponding projectile travels inthe FOV 203 of IR camera 202 and/or based on detection from anotherthreat detection subsystem, the system may determine that such fire isnon-hostile, because the fire is not aimed at helicopter 200, does notpass close enough to helicopter 200, or is not threatening or lethal tothe helicopter 200, for example. Thus, although weapon firing andsubsequent projectile trajectory for actors 201 and 203 are outside theIR camera FOV 203 in FIG. 2A, it may be the case that such firing orcorresponding trajectories are inside the FOV 203, but because acomparison of the respective projectile trajectories indicates theprojectiles will not hit or are not close enough to the helicopter 200,such projectiles are deemed non-threatening and therefore non-hostile.Further, a determination that the projectile is not in its damaging orlethal trajectory stage may also indicate that the projectile is nothostile (i.e., not threatening or lethal). Thus, though all threefirings may be detected, the system can determine that only theprojectile fired from actor 202 is hostile towards helicopter 200.Accordingly, the system can distinguish between hostile fire andnon-hostile fire, as set forth herein. Additionally, as indicated above,one or more fire detection systems may be used in conjunction with theoptical-based hostile fire detection and identification systems,methods, and computer programs products as set forth herein, such assystems that detect a shock wave front of a projectile, that usingmicrophone arrays to detect projectile firing sounds, that analyzechanges in electrostatic environment caused by the projectile around thevehicle, and that perform radar projection of the projectile.

FIG. 2B shows a variation of the scenario in FIG. 2A. In FIG. 2B,helicopter 200 includes a system with eight optical sensors, forinstance, IR sensors (e.g., IR cameras or FPAs), each with acorresponding FOV 203. Use of multiple sensors can provide a greaterdegree of protection, for instance, from hostile fire originating frombehind helicopter 200. FIG. 2B shows that the optical sensors providedrespective FOVs such that the cumulative FOV is 360 degrees or almost360 degrees of coverage. Note further that FIG. 2B indicates that theFOVs do not overlap. However, optionally, one or more of the FOVs mayoverlap one or more adjacent FOVs. Further, note that the representationshown in FIG. 2B is only an example and more or less IR sensors andcorresponding FOVs 203 than shown can be provided. For example, onlyfour FPAs may be used, each having a FOV from 100 to 105 degrees, forinstance, so as to cover or map 180 degrees around the vehicle. Thus,the pixels of the respective FPAs can be mapped to into directions basedon the orientation of their respective FPA and corresponding FOV.Additionally, as indicated above, one or more fire detection systems maybe used in conjunction with the optical-based hostile fire detection andidentification systems, methods, and computer programs products as setforth herein, such as systems that detect a shock wave front of aprojectile, that using microphone arrays to detect projectile firingsounds, that analyze changes in electrostatic environment caused by theprojectile around the vehicle, and that perform radar projection of theprojectile.

Not shown in the example of FIG. 2B, a projectile trajectory may be“seen” by multiple IR sensors. That is, the projectile trajectory maytraverse through FOVs of multiple IR sensors. For example, a centerpixel of an FPA may be aligned with the boresight of the helicopter 200and may “pick up” a portion of the projectile trajectory. Another IRsensor, for instance, an FPA with its center pixel aligned ninetydegrees offset from the boresight-aligned pixel of the foregoing FPA,may see the projectile trajectory differently. The location of both FPAsis relevant, because the projectile may pass within ten meters of onebut twenty meters of the other (if the two are separated by ten meters),for example.

Providing multiple optical sensors may also be for the system to providestereoscopic vision in effect, to determine hostile fire originationdistance and/or to improve accuracy and fidelity. Optionally, projectiledata associated with non-overlapping and/or overlapping FOVs may beautomatically compared to enhance hostile fire indication accuracy. Forexample, a miss distance of a projectile associated with each FOV may becompared and (1) if one miss distance exceeds a predetermined thresholdit is determined that the projectile is hostile (e.g., the correspondingvehicle is the intended target of the projectile) and/or (2) if thetotal of the miss distances is below a predetermined threshold, then theprojectile is determined to be hostile. As another example, two IRsensors may be a known distance apart (e.g., ten meters). Thedifferences in their displays may be used to determine an actual rangeto an origination location or location area for hostile fire. Thus,using known and captured velocity data associated with the projectile,the system may “trace back” to ground (including man-made structures) inorder to determine the distance away and location or location area ofthe hostile fire. Optionally, captured muzzle flash data may becorrelated with the captured projectile trajectory to determine thedistance away and location or location area of the hostile fire.

Further, use of multiple optical sensors can inform the flight crewand/or maintenance personnel likelihood of the vehicle being hit byhostile fire. Such information can be provided in the form of aprobability number, for example. Further, a location or location area ofthe hit may be provided. For example, an indication of hostile firelikely to have hit the vehicle can be provided relative to boresight(e.g., o'clock position) of the vehicle. Optionally, if the probabilitynumber does not exceed a predetermined threshold, the system may notprovide an indication that the vehicle was likely hit by hostile fire.Hit information may be used for in-flight damage identification andassessment. Optionally or alternatively, hit information may be used forpost-flight maintenance.

Accordingly, one or more embodiments of the invention can also includesystems, methods, and computer program products for detectingidentifying hostile fire strikes to a vehicle. The identification can bethat the hostile fire will hit the vehicle, will likely hit the vehicle,hit the vehicle, and/or likely hit the vehicle. In the case ofpredictive hits, a warning or alert subsystem and/or countermeasuresubsystem may be activated. In the case of actual or likely strikes tothe vehicle, such strikes may go unnoticed by occupants of the vehicle,and a travel path of a detected projectile can be mapped to positions orareas on the vehicle, thus identifying a likely position or area ofprojectile impact. As indicated above, such data can be used forin-flight damage assessment as well as for post-flight inspection andmaintenance purposes.

FIG. 8 shows an example of a display 800 providing hostile fire hitprobability information. The display 800 can have indicia associatedwith the hit/likely hit location on the vehicle and also probabilitydata, such as hit probability percentage. Thus, statistical orprobabilistic data of a hit or likely hit can be used to generate anindication for air or maintenance crews that the vehicle was hit and anapproximation or estimation of where the vehicle was hit or likely hit.Again, such data can be used by air and maintenance crews for damageassessment, inspection, and repair. Additionally, optionally, hit datacan be used by vehicle crew or intelligence to retrace their travelpattern to determine where and/or when the vehicle was hit.

Optionally, in one or more embodiments of the invention, hostile firecan be detected and identified at a first vehicle and such determinationcan transmitted from the first vehicle to one or more other vehicles ina network. Information regarding the projectile may be sent to one ormore locations remote from the vehicle, such as another vehicle in anetwork of vehicles. The projectile information can indicate to theremote location(s) that the first vehicle is experiencing hostile fire.Data regarding hostile fire relative to the first vehicle can be storedat one or more of the other vehicles and even retransmitted to othervehicles or base stations. Further, optionally, transmission of firedata can include only muzzle flash data. Fire data shared betweenplatforms can be used to obtain initial or better accuracy regarding thefire and/or its location or location area of origination (e.g., adistance away). In embodiments, one vehicle may receive hit or likelyhit data associated with another vehicle and store such data in memory.Accordingly, the one vehicle may store data regarding projectile impactlocations or likely locations on the another vehicle. This data may beused to assist in identifying why the another vehicle was “downed.”

FIG. 7 is an operational depiction of a network and system, method, andcomputer program product according to one or more embodiments of theinvention.

Referring to FIG. 7, generally speaking, a first helicopter candetermine that it is subject to hostile fire from actor 202 as shown anddescribed herein and transmit such data to another helicopter 250 in anetwork. The second helicopter 250 can take appropriate action oractions without having to make its own hostile fire detection anddetermination, for example. Accordingly, optionally, the secondhelicopter may or may not need to be outfitted with the relatively heavysensing equipment and can rely on another helicopter to indicate thatthey have entered a hostile zone. For helicopters both having thissensor equipment, geolocation of the hostile fire can be determinedbased on communications between the two systems.

In view of the foregoing structural and functional features describedabove, methods 400, 500, and 600 in accordance with one or moreembodiments of the invention will now be described with respect to FIGS.4, 5, and 6. While, for purposes of simplicity of explanation, themethodologies of FIGS. 4, 5, and 6 are shown and described as executingserially, it is to be understood and appreciated that the invention isnot limited by the illustrated order, as some aspects or steps could, inaccordance with the present invention, occur in different orders and/orconcurrently with other aspects from that shown and described herein.Moreover, not all illustrated features may be required to implement amethod or methods in accordance with one or more embodiments of theinvention.

FIG. 4 is a flow chart for a method 400 according to one or moreembodiments of the invention.

Method 400 can detect or capture projectile data, for instance,projectile trajectory data as set forth herein 402. The data can bedetected or captured electronically, for instance, via an infrareddetection device, such as an IR camera, also called a focal plane array(FPA). The detected or captured data can be processed, for instance, todetermine a travel path or trajectory of the projectile 404. Based ontravel path or trajectory data, for example, a determined miss distanceof the projectile, it is determined that the projectile is hostile(e.g., the corresponding vehicle was the intended target) of theprojectile 406. Continuous detection and capture of projectile data canbe performed. If it is determined that the projectile is hostile, ahostile fire indication may be provided, such as an electronic warning,for instance an audible, visual, and/or tactile warning or indication408. The indication may indicate that the projectile is hostile (or evenfriendly), depending upon a determined miss distance from the vehicle,for example. Optionally, additional actions may be performed, such asmoving the vehicle in response to the determination, deployingcountermeasures, deploying weapon systems, and/or communicatingprojectile data and/or determinations based on the projectile data toone or more remote locations, such as another vehicle or vehicles 410.Any of the aforementioned additional actions may be performedautomatically in response to a hostile fire determination.

FIG. 5 is a flow chart for a method 500 according to one or moreembodiments of the invention.

Method 500 is similar to method 400 of FIG. 4, but expressly indicatesthat the captured and processed trajectory data is used to determinewhether the projectile will hit or will likely hit the vehicle 506. Suchhit determination can be used to provide a timely indication, such as anelectronic warning, for instance an audible, visual, and/or tactilewarning or indication, that the vehicle will be hit or will likely behit 508. In response to the indication, additional actions can beundertaken by the vehicle, such as taking evasive maneuvers, deployingcountermeasures and/or deploying weapon systems 510. Additionally,projectile data and hit data may be transmitted to a location remotefrom the vehicle. Such data may be used, for example, in the unfortunateevent that the vehicle is disabled, in order to determine a location ofthe vehicle and/or a reason or likely reason why the vehicle becamedisabled.

FIG. 6 is a flow chart for method 600 according to one or moreembodiments of the invention.

Method 600 is similar to method 500 of FIG. 5, but determines, based onthe captured and processed projectile trajectory data, whether theprojectile hit or likely hit the vehicle 606. Such hit or likely hitdata can be representative of a calculation to obtain a probabilitynumber of hit or likely hit (or even a near miss). In response to theindication, additional actions can be undertaken. For example, thevehicle can alter its path. As another example, a determination can bemade as to the location or area on the vehicle at which the projectilehit or likely hit the vehicle. Such hit or likely hit location data canbe used to perform in-flight damage assessment by aircrew and/orpost-flight inspection and maintenance, if necessary, to the vehicleupon returning from hostile areas.

It will be appreciated that portions (i.e., some, none, or all) of thecircuits, circuitry, modules, processes, sections, systems, and systemcomponents described herein can be implemented in hardware, hardwareprogrammed by software, software instructions stored on a non-transitorycomputer readable medium or a combination of the above.

For example, the processor can include, but is not be limited to, apersonal computer or workstation or other such computing system thatincludes a processor, microprocessor, microcontroller device, or iscomprised of control logic including integrated circuits such as, forexample, an Application Specific Integrated Circuit (ASIC). Theinstructions can be compiled from source code instructions provided inaccordance with a programming language such as Java, C++, C#.net or thelike. The instructions can also comprise code and data objects providedin accordance with, for example, the Visual Basic™ language, or anotherstructured or object-oriented programming language. The sequence ofprogrammed instructions and data associated therewith can be stored in anon-transitory computer-readable medium such as a computer memory orstorage device which may be any suitable memory apparatus, such as, butnot limited to ROM, PROM, EEPROM, RAM, flash memory, disk drive and thelike.

Furthermore, the circuits, circuitry, modules, processes, systems,sections, and system components can be implemented as a single processoror as a distributed processor. Further, it should be appreciated thatthe steps mentioned above may be performed on a single or distributedprocessor (single and/or multi-core). Also, the processes, modules, andsub-modules described in the various figures of and for embodimentsabove may be distributed across multiple computers or systems or may beco-located in a single processor or system. Exemplary structuralembodiment alternatives suitable for implementing the circuits,circuitry, modules, sections, systems, system components, means, orprocesses described herein are provided below.

The circuits, circuitry, modules, processors, systems, or systemcomponents described herein can be implemented as a programmed generalpurpose computer, an electronic device programmed with microcode, ahard-wired analog logic circuit, software stored on a computer-readablemedium or signal, an optical computing device, a networked system ofelectronic and/or optical devices, a special purpose computing device,an integrated circuit device, a semiconductor chip, and a softwaremodule or object stored on a computer-readable medium or signal, forexample.

Embodiments of the method and system (or their components or modules),may be implemented on a general-purpose computer, a special-purposecomputer, a programmed microprocessor or microcontroller and peripheralintegrated circuit element, an ASIC or other integrated circuit, adigital signal processor, a hardwired electronic or logic circuit suchas a discrete element circuit, a programmed logic circuit such as a PLD,PLA, FPGA, PAL, or the like. In general, any processor capable ofimplementing the functions or steps described herein can be used toimplement embodiments of the method, system, or a computer programproduct (software program stored on a non-transitory computer readablemedium).

Furthermore, embodiments of the disclosed method, system, and computerprogram product may be readily implemented, fully or partially, insoftware using, for example, object or object-oriented softwaredevelopment environments that provide portable source code that can beused on a variety of computer platforms. Alternatively, embodiments ofthe disclosed method, system, and computer program product can beimplemented partially or fully in hardware using, for example, standardlogic circuits or a VLSI design. Other hardware or software can be usedto implement embodiments depending on the speed and/or efficiencyrequirements of the systems, the particular function, and/or particularsoftware or hardware system, microprocessor, or microcomputer beingutilized. Embodiments of the method, system, and computer programproduct can be implemented in hardware and/or software using any knownor later developed systems or structures, devices and/or software bythose of ordinary skill in the applicable art from the functiondescription provided herein and with a general basic knowledge of theuser interface and/or computer programming arts.

Having now described embodiments of the disclosed subject matter, itshould be apparent to those skilled in the art that the foregoing ismerely illustrative and not limiting, having been presented by way ofexample only. Thus, although particular configurations have beendiscussed herein, other configurations can also be employed. Numerousmodifications and other embodiments (e.g., combinations, rearrangements,etc.) are enabled by the present disclosure and are within the scope ofone of ordinary skill in the art and are contemplated as falling withinthe scope of the disclosed subject matter and any equivalents thereto.Features of the disclosed embodiments can be combined, rearranged,omitted, etc., within the scope of the invention to produce additionalembodiments. Furthermore, certain features may sometimes be used toadvantage without a corresponding use of other features. Accordingly,Applicants intend to embrace all such alternatives, modifications,equivalents, and variations that are within the spirit and scope of thepresent invention.

1. A system that is operative during the day and at night to determinewhether a position is an intended target of a fired unguided energeticprojectile, the system comprising: an infrared (IR) camera mountable atthe position, said IR camera having a field of view (FOV) and apredetermined sensitivity sufficient to capture a heat signature of thefired unguided energetic projectile, the heat signature including atleast one of a firing component generated upon firing of the projectileand a friction component generated by friction as the projectile travelsthrough the troposphere, pixels of said IR camera being operative tocapture a portion of a trail of energy associated with the heatsignature of the fired projectile; and an image processor operative toreceive signals from said IR camera corresponding to the capturedportion of the trail of energy, said image processor being operative topost-process in near real time the signals from said IR camera and tomake a determination as to whether the position was the intended targetof the fired projectile by analyzing calculated vertical and horizontalmiss distances of the fired projectile, the vertical and horizontal missdistances being calculated based on a product of vertical and horizontalpixel trails, respectively, in the captured portion of the trail ofenergy as functions of time and projectile velocity.
 2. The systemaccording to claim 1, comprising an alert system operatively coupled tosaid image processor to generate timely audible and visible indicationsthat the position is the intended target of the fired projectile basedon the determination by said image processor that the position was theintended target of the fired projectile.
 3. The system according toclaim 1, wherein said IR camera is calibrated so as to set one or moremiss distance thresholds indicative of hostile fire based on knownvelocities or velocity ranges of select known-to-be hostile projectilesand corresponding distance ranges of said projectiles.
 4. The systemaccording to claim 1, wherein the position is one of a helicopter, aship, aircraft, a ground vehicle, a building, and a person.
 5. Thesystem according to claim 1, further comprising a countermeasure systemmountable at the position that is operative to deploy one of anon-lethal weapon, a soft-kill, and a hard-kill weapon in response tothe determination that the position was the intended target of the firedprojectile, the weapon being deployed to a determined location orlocation area associated with the fired projectile, wherein thedetermined location or location area is determined based on the signalsfrom said IR camera corresponding to the captured portion of the trailof energy.
 6. The system according to claim 5, wherein the determinedlocation or location area is determined based on the signals from saidIR camera corresponding to the captured portion of the trail of energyand also based on signals from an other IR camera of the system, saidother IR camera having a field of view (FOV) and a predeterminedsensitivity sufficient to capture a heat signature of the fire unguidedenergetic projectile from the perspective of said other IR camera, theheat signature from the perspective of said other IR camera including atleast one of a firing component generated upon firing of the projectileand a friction component generated by friction as the projectile travelsthrough the troposphere, pixels of said other IR camera being operativeto capture a portion of a trail of energy associated with the heatsignature of the fired projectile from the perspective of said other IRcamera, and wherein the determined location or location area is anorigination location or location area of the unguided energeticprojectile and said image processor is configured and operative toprocess signals from said IR camera and signals from said other IRcamera to determine a distance to the origination location or locationarea of the unguided energetic projectile.
 7. The system according toclaim 1, comprising said IR camera and at least one more of said IRcameras, each of said IR cameras having a FOV, the FOVs combining toform a total FOV for the system.
 8. The system according to claim 1,wherein the system is configured and operative to determine whether theprojectile will hit, will likely hit, did hit, and/or did likely hit theposition.
 9. The system according to claim 1, wherein the system isconfigured to represent the captured portion of the trail of energy as atwo-dimensional representation over time, and wherein the functions oftime and projectile velocity include a rate of change of the projectiletrace and the rate of rate of change of the projectile trace. 10-17(canceled)
 18. A nontransitory computer readable storage medium havingstored thereon software instructions that, when executed by a processor,cause the processor to perform operations comprising: analyze receivedelectronic data regarding a sensed heat signature of an unguidedprojectile; and determining a miss distance of the unguided projectilebased on the analyzed received electronic data, the miss distance beingat least one of a vertical miss distance and a horizontal miss distance.19. The nontransitory computer readable storage medium according toclaim 18, wherein the received electronic data is from an IR camera thatcaptures the sensed heat signature of the unguided projectile, the missdistance being calculated based on a product of the rate of projectilevelocity change and the rate of rate of change.
 20. The nontransitorycomputer readable storage medium according to claim 18, wherein thestored software instructions, when executed by the processor, cause theprocessor to perform operations comprising: responsive to the determinedmiss distance of the unguided projectile, identify whether or not theunguided projectile is hostile or friendly; and in the case of a hostileidentification, output an indication that the unguided projectile ishostile.
 21. The nontransitory computer readable storage mediumaccording to claim 18, wherein the heat signature is sensed byelectronically detecting infrared radiation of the projectile in a fieldof view (FOV); and wherein the determining the miss distance is furtherbased on electronically stored data for one or more projectile types.22. The nontransitory computer readable storage medium according toclaim 21, wherein the electronically stored projectile type dataincludes, for each type of projectile, projectile velocity data andprojectile distance data.
 23. The system according to claim 1, whereinthe miss distances are calculated based further on electronically storeddata for one or more projectile types.
 24. The system according to claim23, wherein the electronically stored projectile type data includes, foreach type of projectile, projectile velocity data and projectiledistance data.